I couldn't wait for my beautiful wooden version, so I threw together the modification with cardboard -- which is well dampened wood after all, right?
My initial impression were somewhat complex -- I thought, right out of the box, that there was way too much treble energy now, so much so, that I had to reduce the tweeter the full -3db in the ASP -- and still it was bright and shifted upwards -- so I reduced it still further using the amp voltage gain control another -2db -- now we were talking.
I put on Waylon Jennings "The Outlaws" -- just something I had handy, and boy -- was I floored -- stage presence and width like you have never heard. Diana Krall "The Girl in the Next Room" faired even better. But this was only after about an hour of struggling with the positioning in my small apartment – the new tweeter made this VERY difficult , especially the out of phase portion - I had to use the RR/XLO in-phase, out of phase tracks to get the voice dead centered -- when this was done, fantastic results! Huge sound stage (but unexaggerated), and surprisingly the bass transient were now much better localized – you could hear the first high frequency smack on the skin of the drum, followed by the low bass notes – and you could pin-point where it was coming from – neat effect. It really bowled me over with the NAXOS Aaron Copland RODEO with the Buffalo Symphony Orchestra – you really were in the concert hall. But I have a felling that this will not be for everyone.